Commit Graph

17 Commits

Author SHA1 Message Date
Junio C Hamano
2f6128daab Merge branch 'gs/rebase-allow-empty-message'
"git rebase" learned to take "--allow-empty-message" option.

* gs/rebase-allow-empty-message:
  rebase: add --allow-empty-message option
2018-02-21 12:45:04 -08:00
Junio C Hamano
0f57f731ea Merge branch 'pw/sequencer-in-process-commit'
The sequencer infrastructure is shared across "git cherry-pick",
"git rebase -i", etc., and has always spawned "git commit" when it
needs to create a commit.  It has been taught to do so internally,
when able, by reusing the codepath "git commit" itself uses, which
gives performance boost for a few tens of percents in some sample
scenarios.

* pw/sequencer-in-process-commit:
  sequencer: run 'prepare-commit-msg' hook
  t7505: add tests for cherry-pick and rebase -i/-p
  t7505: style fixes
  sequencer: assign only free()able strings to gpg_sign
  sequencer: improve config handling
  t3512/t3513: remove KNOWN_FAILURE_CHERRY_PICK_SEES_EMPTY_COMMIT=1
  sequencer: try to commit without forking 'git commit'
  sequencer: load commit related config
  sequencer: simplify adding Signed-off-by: trailer
  commit: move print_commit_summary() to libgit
  commit: move post-rewrite code to libgit
  Add a function to update HEAD after creating a commit
  commit: move empty message checks to libgit
  t3404: check intermediate squash messages
2018-02-13 13:39:15 -08:00
Genki Sky
a6c612b528 rebase: add --allow-empty-message option
This option allows commits with empty commit messages to be rebased,
matching the same option in git-commit and git-cherry-pick. While empty
log messages are frowned upon, sometimes one finds them in older
repositories (e.g. translated from another VCS [0]), or have other
reasons for desiring them. The option is available in git-commit and
git-cherry-pick, so it is natural to make other git tools play nicely
with them. Adding this as an option allows the default to be "give the
user a chance to fix", while not interrupting the user's workflow
otherwise [1].

  [0]: https://stackoverflow.com/q/8542304
  [1]: https://public-inbox.org/git/7vd33afqjh.fsf@alter.siamese.dyndns.org/

To implement this, add a new --allow-empty-message flag. Then propagate
it to all calls of 'git commit', 'git cherry-pick', and 'git rebase--helper'
within the rebase scripts.

Signed-off-by: Genki Sky <sky@genki.is>
Reviewed-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-02-07 11:26:46 -08:00
Phillip Wood
28d6daed4f sequencer: improve config handling
The previous config handling relied on global variables, called
git_default_config() even when the key had already been handled by
git_sequencer_config() and did not initialize the diff configuration
variables. Improve this by: i) loading the default values for message
cleanup and gpg signing of commits into struct replay_opts;
ii) restructuring the code to return immediately once a key is
handled; and iii) calling git_diff_basic_config(). Note that
unfortunately it is not possible to return early if the key is handled
by git_gpg_config() as it does not indicate to the caller if the key
has been handled or not.

The sequencer should probably have been calling
git_diff_basic_config() before as it creates a patch when there are
conflicts. The shell version uses 'diff-tree' to create the patch so
calling git_diff_basic_config() should match that. Although 'git
commit' calls git_diff_ui_config() I don't think the output of
print_commit_summary() is affected by anything that is loaded by that
as print_commit_summary() always turns on rename detection so would
ignore the value in the user's configuration anyway. The other values
loaded by git_diff_ui_config() are about the formatting of patches so
are not relevant to print_commit_summary().

Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-12-13 11:15:14 -08:00
Liam Beguin
d8ae6c84da rebase -i: learn to abbreviate command names
`git rebase -i` already know how to interpret single-letter command
names. Teach it to generate the todo list with these same abbreviated
names.

Based-on-patch-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Liam Beguin <liambeguin@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-12-05 10:20:51 -08:00
Liam Beguin
0cce4a2756 rebase -i -x: add exec commands via the rebase--helper
Recent work on `git-rebase--interactive` aims to convert shell code to
C. Even if this is most likely not a big performance enhancement, let's
convert it too since a coming change to abbreviate command names
requires it to be updated.

Signed-off-by: Liam Beguin <liambeguin@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-12-05 10:20:51 -08:00
Liam Beguin
313a48eaca rebase -i: update functions to use a flags parameter
Update functions used in the rebase--helper so that they take a generic
'flags' parameter instead of a growing list of options.

Signed-off-by: Liam Beguin <liambeguin@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-12-05 10:20:51 -08:00
Liam Beguin
d80fc29367 rebase -i: replace reference to sha1 with oid
Since we are trying to abstract the hash function name elsewhere in the
code base, lets use OID instead of SHA-1 in the rebase--helper too.

Signed-off-by: Liam Beguin <liambeguin@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-12-05 10:20:50 -08:00
Liam Beguin
8dccc7a6b2 rebase -i: refactor transform_todo_ids
The transform_todo_ids function is a little hard to read. Lets try
to make it easier by using more of the strbuf API. Also, since we'll
soon be adding command abbreviations, let's rename the function so
it's name reflects that change.

Signed-off-by: Liam Beguin <liambeguin@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-12-05 10:20:50 -08:00
Phillip Wood
b36c590813 sequencer: load commit related config
Load default values for message cleanup and gpg signing of commits in
preparation for committing without forking 'git commit'. Note that we
interpret commit.cleanup=scissors to mean COMMIT_MSG_CLEANUP_SPACE to
be consistent with 'git commit'

Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-11-24 22:44:18 +09:00
Johannes Schindelin
c44a4c650c rebase -i: rearrange fixup/squash lines using the rebase--helper
This operation has quadratic complexity, which is especially painful
on Windows, where shell scripts are *already* slow (mainly due to the
overhead of the POSIX emulation layer).

Let's reimplement this with linear complexity (using a hash map to
match the commits' subject lines) for the common case; Sadly, the
fixup/squash feature's design neglected performance considerations,
allowing arbitrary prefixes (read: `fixup! hell` will match the
commit subject `hello world`), which means that we are stuck with
quadratic performance in the worst case.

The reimplemented logic also happens to fix a bug where commented-out
lines (representing empty patches) were dropped by the previous code.

While at it, clarify how the fixup/squash feature works in `git rebase
-i`'s man page.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-27 15:35:06 -07:00
Johannes Schindelin
cdac2b01ff rebase -i: skip unnecessary picks using the rebase--helper
In particular on Windows, where shell scripts are even more expensive
than on MacOSX or Linux, it makes sense to move a loop that forks
Git at least once for every line in the todo list into a builtin.

Note: The original code did not try to skip unnecessary picks of root
commits but punts instead (probably --root was not considered common
enough of a use case to bother optimizing). We do the same, for now.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-27 15:35:05 -07:00
Johannes Schindelin
943999493f rebase -i: check for missing commits in the rebase--helper
In particular on Windows, where shell scripts are even more expensive
than on MacOSX or Linux, it makes sense to move a loop that forks
Git at least once for every line in the todo list into a builtin.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-27 15:35:05 -07:00
Johannes Schindelin
3546c8d927 rebase -i: also expand/collapse the SHA-1s via the rebase--helper
This is crucial to improve performance on Windows, as the speed is now
mostly dominated by the SHA-1 transformation (because it spawns a new
rev-parse process for *every* line, and spawning processes is pretty
slow from Git for Windows' MSYS2 Bash).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-27 15:35:05 -07:00
Johannes Schindelin
62db524779 rebase -i: generate the script via rebase--helper
The first step of an interactive rebase is to generate the so-called "todo
script", to be stored in the state directory as "git-rebase-todo" and to
be edited by the user.

Originally, we adjusted the output of `git log <options>` using a simple
sed script. Over the course of the years, the code became more
complicated. We now use shell scripting to edit the output of `git log`
conditionally, depending whether to keep "empty" commits (i.e. commits
that do not change any files).

On platforms where shell scripting is not native, this can be a serious
drag. And it opens the door for incompatibilities between platforms when
it comes to shell scripting or to Unix-y commands.

Let's just re-implement the todo script generation in plain C, using the
revision machinery directly.

This is substantially faster, improving the speed relative to the
shell script version of the interactive rebase from 2x to 3x on Windows.

Note that the rearrange_squash() function in git-rebase--interactive
relied on the fact that we set the "format" variable to the config setting
rebase.instructionFormat. Relying on a side effect like this is no good,
hence we explicitly perform that assignment (possibly again) in
rearrange_squash().

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-27 15:35:05 -07:00
Brandon Williams
b2141fc1d2 config: don't include config.h by default
Stop including config.h by default in cache.h.  Instead only include
config.h in those files which require use of the config system.

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-15 12:56:22 -07:00
Johannes Schindelin
4557f1add2 rebase--helper: add a builtin helper for interactive rebases
Git's interactive rebase is still implemented as a shell script, despite
its complexity. This implies that it suffers from the portability point
of view, from lack of expressibility, and of course also from
performance. The latter issue is particularly serious on Windows, where
we pay a hefty price for relying so much on POSIX.

Unfortunately, being such a huge shell script also means that we missed
the train when it would have been relatively easy to port it to C, and
instead piled feature upon feature onto that poor script that originally
never intended to be more than a slightly pimped cherry-pick in a loop.

To open the road toward better performance (in addition to all the other
benefits of C over shell scripts), let's just start *somewhere*.

The approach taken here is to add a builtin helper that at first intends
to take care of the parts of the interactive rebase that are most
affected by the performance penalties mentioned above.

In particular, after we spent all those efforts on preparing the sequencer
to process rebase -i's git-rebase-todo scripts, we implement the `git
rebase -i --continue` functionality as a new builtin, git-rebase--helper.

Once that is in place, we can work gradually on tackling the rest of the
technical debt.

Note that the rebase--helper needs to learn about the transient
--ff/--no-ff options of git-rebase, as the corresponding flag is not
persisted to, and re-read from, the state directory.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-02-09 14:55:26 -08:00